Safety Measurement System

Measure vs. Percentile

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. Expand for more information.

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure only considers individual performance based on 24 months of data, with a measure of 0 indicating best performance. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. The graph below shows how the carrier’s measure correlates with its percentile rank over a selected period of time.

Measure

Percentile

Measure	Percentile
0	0
0.04	1
0.04	2
0.05	3
0.06	4
0.07	5
0.08	6
0.09	7
0.10	8
0.11	9
0.13	10
0.14	11
0.16	12
0.17	13
0.19	14
0.21	15
0.22	16
0.24	17
0.25	18
0.27	19
0.28	20
0.30	21
0.31	22
0.33	23
0.35	24
0.37	25
0.38	26
0.40	27
0.41	28
0.43	29
0.45	30
0.47	31
0.48	32
0.51	33
0.53	34
0.54	35
0.56	36
0.59	37
0.61	38
0.63	39
0.65	40
0.67	41
0.69	42
0.71	43
0.74	44
0.76	45
0.78	46
0.80	47
0.83	48
0.85	49
0.88	50
0.90	51
0.92	52
0.95	53
0.97	54
1.01	55
1.04	56
1.07	57
1.10	58
1.13	59
1.16	60
1.19	61
1.23	62
1.26	63
1.30	64
1.34	65
1.38	66
1.41	67
1.45	68
1.50	69
1.54	70
1.58	71
1.63	72
1.68	73
1.72	74
1.78	75
1.84	76
1.89	77
1.95	78
2.01	79
2.06	80
2.13	81
2.18	82
2.26	83
2.35	84
2.44	85
2.54	86
2.65	87
2.76	88
2.87	89
3.01	90
3.14	91
3.31	92
3.48	93
3.68	94
3.92	95
4.19	96
4.57	97
5.05	98
5.87	99
11.32	100